Fabric draw-off mechanism



March 17, 1970 PEBERDY 3,500,664

FABRIC DRAW-OFF MECHANISM I Filed April 26, 1967 2 Sheets-Sheet 1 March17, 1970 R. PEBERDY FABRIC DRAW-OFF. MECHANISM 2 Sheets-Sheet 2 FiledApril 26. 1967 United States Patent 3,500,664 FABRIC DRAW-OFF MECHANISMRoland Peberdy, Leicester, England, assignor to The Bentley EngineeringCompany Limited, Leicester, England Filed Apr. 26, 1967, Ser. No.633,736 Claims priority, application Great Britain, Apr. 30, 1966,19,093/ 66 Int. Cl. D04b 27/14 U.S. Cl. 66-150 8 Claims ABSTRACT OF THEDISCLOSURE Fabric tensioning means in 'a circular knitting machinehaving a succession of tensioning members formed by wheels arranged in acircular row above and around the throat of a needle cylinder, thewheels being of toothed form and engaging in the helical thread of acommon central worm so that relative rotation between the needlecylinder and the worm causes the tensioning wheels to be rotated and byengagement with fabric close to the needles draws the fabric away fromthe needles. To avoid reverse turning movement of the tensioning wheelsduring a reverse swing in reciprocatory knitting, ratchet means isprovided to eliminate relative turning movement between the needlecylinder and the worm during such reverse swing.

This invention relates to mechanism for drawing otr fabric from circularknitting machines and is particularly suitable for machines adapted toknit articles, such as socks or stockings, separately and shedindividual articles from the needles as they are completed.

In accordance with the invention there is provided in a circularknitting machine, fabric tensioning means comprising a succession oftensioning members positioned within and around the needle circle andhaving fabric engaging exteriors which are caused to bear downwardlyagainst fabric as it is produced and to move around closed paths in suchdirections and in such manner as to draw the fabric inwardly from theneedles at a desired tension. Conveniently the tensioning members arespaced apart in a circular row around the axis of the needle cylinder orcylinders and positioned immediately above the cylinder throat of asingle cylinder machine or the throat of the bottom cylinder of a doublecylinder machine. They may be urged resiliently individually towardssuch throat so as to press against fabric resting thereon. The tensionmembers may be operated by a common drive means positioned within theneedle circle.

In a convenient construction the tensioning members are constituted byrotatable wheels. Such wheels may be toothed wheels arranged around andengaging a common driving worm. In rotating cylinder machines such adriving worm is fixed during knitting and the toothed wheels rotatebodily around it together with the needles, the sinkers, etc. and thefabric, and so are rotated about their own axes to draw off the fabric.In rotating cam box machines such a driving worm will rotate with thecam box during knitting and so will rotate the toothed wheels, abouttheir axes, the mountings of the toothed wheels being stationary inrelation to the machine as a whole. In either case, the driving worm orits supporting means should be fitted with ratchet means so arrangedthat when knitting by reciprocation is performed, there is no relativeturning movement between the driving worm and the toothed wheelsengaging with it and therefore no turning of the toothed wheels when therelative turning movement between the needle cylinder and the cam box is3,500,664 Patented Mar. 17, 1970 in the opopsite direction to that ofnormal continuous rotary knitting.

The tensioning members are preferably individually adjustable as to thepressure with which they are urged into engagement with the fabric.

The invention further provides in a circular knitting machine fabrictensioning means as aforementioned assembled as a unit of substantiallycylindrical over-all form locatable axially within the upper needlecylinder of a double cylinder machine. The unit may incorporate thetensioning members and carriers thereforepermitting individual operativemovement of the tensioning members. Means may be provided for adjustmentof pressure applied resiliently to the tensioning members which meansmay be adapted for actuation form above for example through the uppercylinder cover plate of a double cylinder machine or through a cylindercap of a single cylinder machine.

The tensioning members are desirably positioned in close proximity tothe sinkers of the machine so as to be capable of drawing off fabric assoon as the first few courses are knitted when setting up the fabric onthe needles.

The invention is illustrated by way of example in the accompanyingdrawings showing mechanism according to the invention applied to adouble cylinder circular knitting machine. In the drawings:

FIGURE 1 is a part-section view in elevation of the knitting headassembly omitting certain parts particularly in the lower cylinder whichhave no direct relation to the mechanism of this invention;

FIGURE 2 is a cross-sectional plan view taken on the line II-II inFIGURE 1; and

FIGURE 3 is a cross-sectional plan view taken on the line IIIIIIIIIIIIin FIGURE 1.

Mechanism in accordance with the invention is shown in FIGURE 1 mountedinside an upper needle cylinder 1 of a double cylinder circular knittingmachine of the rotary cylinder type. Other parts of the machine comprisethe lower needle cylinder 2, upper and lower cam boxes 3 and 4, needlecams S and 6, needle sliders 7 and 8, needles 9 an intermediate plate10, hearing housing 11, drive gear 12, a thrust race 14 and top bedplate 15. The machine has inside sinkers 49 controlled by sinker camssuch as 50, the top surface of which is slightly hollowed forcooperation with fabric engaging and tensioning members about to bedescribed.

With particular reference to FIGURE 1, mechanism for drawing off fabricfrom the needles as it is produced comprises a number of fabric engagingand tensioning members formed by toothed wheels 18 all engaging a commondriving worm 38 secured to a tube 37 which is fixed axially in themachine and prevented from rotating during knitting. The teeth of thewheels 18 provide fabric engaging exteriors which move around closedcircular paths when the wheels rotate.

Each toothed wheel 18 is mounted so that its general plane extendsradially of the axis of the needle cylinders (see FIGURE 3), beingcarried on a spindle 19 between the forked ends 20a of a plunger 20. Theforked ends 20a have slanted end faces (as seen in FIG. 1) to liesubstantially parallel to the bottom cylinder throat to facilitate thepassage of knitted fabric below them. Each plunger 20 has a shank 200which is slidable in the bore of an adjustment member 22. The adjustmentmember 22 is screw threaded in a sleeve 17 and rotatable by ascrewdriver (which may be applied through a hole. 131: in the topcylinder cover plate 13) engaging a slot 22a in the top of member 22. Aspring 23 surrounds the shank 20c of the plunger 20 abutting the end ofthe adjustment member 22 and urging the plunger 20 and thus theasociated wheel 18 into engagement with the knitted fabric.

The toothed wheels 18 and the associated adjustment levices justdescribed are mounted on a cylindrical block 16 having tricks for vergeelements 24 and an annular groove for butts 24a of the verge elements24. To the )lock 16 is secured a plate ring 21 which projects from heblock 16 and so provides a stop for the plunger 20. iotation of theplungers on their own axes is prerented by flats 20b engaging with thering 21. The block L6 is bolted onto a flanged collar. 26 which islocked my means of a pin 27 onto a tube 25. The tube sur- 'ounds and isrotatable with respect to the aforesaid tube l7. The tube 25 issupported at its upper part by a spring 59 through the medium of a driveblock and in turn .upports the tube 37 through a collar 39 secured to hetube 37. A spring 41 fills the space between the drivng worm 38 and thebottom of the tube 25 so as to allow he block 16 and the verge elements24 to be lowered without locking the wheels 18 between the drive worm l8and sinker earns 50. A control member 51 is fixed to he bottom of thedrive worm 38.

The upper end of the tube 25 is slidable in a bush 28 secured by screws34 to the cover plate 13. The bush B8 is forked at 284 (FIGURE 2) and inthe forks are adjustment screws 33, bearing on a lug 30a on the drive)lock 30. Both the adjustment screws 33 are adjusted to nove the lug3011 between the forks 28a for the circumv 18 do not turn and so do nottend to push the fabric back towards the needles during such reversestroke.

It will be evident that other fabric tensioning members, such as plainrollers, rotary brushes, or endless bands or chains running round pairsof rollers or sprockets of small diameter one of each pair of which isdriven, may be employed in place of the toothed wheels 18.

What I claim is:

1. In a circular knitting machine having a needle cylinder, fabrictensioning means comprising, in combination, tensioning membersconstituted by rotatable wheels mounted in succession within and aroundthe needle circle, said tensioning members having fabric engagingexteriors and including means permitting said exteriors to move aroundclosed paths in upstanding planes extendindividual to each tensioningmember for operating said tensioning members individually to applytension to the fabric as it is produced.

ferential adjustment of the tube 25 and (through the Block 16) of theverge'elements 24 in order to position hem accurately between theneedles. The tube 25 has 1 drive key 32 coupling it to the drive block30 which is also secured to the tube 25 by screws 31. The spring 29nests in a recess in the bush 28. Above the drive block 2. A combinationaccording to claim 1 wherein the mounting means carries the tensioningmembers spaced apart in said needle circle around the axis of the needlecylinder.

3. A combination according to claim 1 wherein said operating means urgesthe tensioning members resiliently and inwardly towards the throat ofthe needle cylinder so as to press against fabric resting on saidthroat.

4. A combination according to claim 1 having a common drive meanspositioned within the needle circle for operating all of the tensioningmembers.

5. A combination according to claim 1 wherein the tensioning members aretoothed wheels, and wherein there is provided a common driving wormwithin the wheels for rotating them.

collar 39 is a cover plate secured to the bottom of the circular block42 which is clamped to the tube 37 by a clamping screw and nut 43. Theblock 42 has a flange 42g and a spigot 42b which engage a ratchet plate44, best illustrated in FIGURE 2, secured to a post 46 mounted on aplatform 47. The ratchet plate 44 is provided with a notch 44a (FIGURE2) and the spigot 42b has a spring loaded plunger 48 of square crosssection, one end of which is in contact with the bore of the ratchetplate 44. The notch 44a is cut in such a manner as to engage the plunger48 and prevent rotation of the block 42 and thus of the tube 37anti-clockwise in FIGURE 2 but not clockwise.

During knitting the tube 37 and thus the drive worm 38. are heldstationary and the toothed wheels 18 rotate bodily around it togetherwith the needles 9, the sinkers 49 etc. and the fabric. Thus the toothedwheels 18 are rotated anti-clockwise in the aspect of the wheel seen inFIGURE 1 and draw the fabric as it is produced away from the needles 9in towards the centre of the lower needle cylinder 2. When the needlecylinders have a to and fro turning movement for performing knitting byreciprocation, the worm 38 is carried around with the remainder of themechanism in the reverse stroke (i.e. the stroke in the directionopposite to that of normal continuous rotary knitting) being driven by'bodily revolving m m t 9 w lled h els 18 a d so he o h w el 6. Acombination according to claim 5 having associated with the driving wormratchet means organised to permit relative turning movement between thedriving worm and toothed wheels driven thereby only in the direction ofnormal continuous rotary knitting.

7. A combination according to claim 1 having means forindividuallyadjusting the pressure of said tensioningmembers.

8.; A combination according to claim 1 having the fabric tensioningmechanism constructed as a unit of substantially cylindrical overallform having a diameter less than the internal'diameter of the needlecylinder.

References Cited UNITED STATES PATENTS 3,380,266 4/1968 Williamson et al6615O 1,641,101 8/1927 Scott 66l49 XR 2,017,082 10/1935 Warren 66-1532,137,362 11/1938 Smith et a1. 66--149 XR 2,696,252 12/1954 Rosen66--153 XR 3,003,342 10/1961 Kent et a1. 66-150 FOREIGN PATENTS 3 1/1890Great Britain. 223,282 11/ 1942 Switzerland.

WM. CARTER REYNOLDS, Primary Examiner US- C ,R. 6- 53

